Fendt 4.1.65 – Transmission Control Module: Actuation fault or Supply failure (Y006 or Y051)

The system has detected a break in the wiring, a short circuit, or a lack of voltage supply preventing the proper actuation of the engine exhaust brake or the cardan brake relay.

• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 916 Vario
• 920 Vario
• 924 Vario
• 926 Vario
• 930 Vario
• Fendt Farmer 400 series
• Fendt Favorit 700 and 900 series
• Fendt 300, 400, 700, 800, and 900 Vario series (including COM III generation models)

1. 1

   Inspect wiring and connectors for a cable break or short circuit between the Transmission Control Module and the Y006 solenoid / Y051 relay, specifically checking separation point X1679 on the right side of the engine bulkhead

2. 2

   Measure supply voltage at the Y006 solenoid valve (Ignition OFF: 0 VDC, Ignition ON: 14 VDC, Engine running/brake not activated: approx. 2.8 VDC)

3. 3

   Test the S047 engine brake switch to ensure it is sending the correct activation signal to the module

4. 4

   Test the Y051 cardan brake relay for internal coil failure or burnt/stuck contacts

1. 1

   Power Down

   Turn off the ignition and disconnect the battery to prevent electrical shorts during the repair.

2. 2

   Access the Components

   For the Y006 Solenoid Valve, access the right side of the tractor near the engine bulkhead. For the Y051 Relay, access the main electrical relay/fuse board.

3. 3

   Repair Wiring

   If the diagnostic checks revealed damaged wires or corroded pins at connector X1679, clean the contacts with electrical contact cleaner or splice in new wiring as necessary.

4. 4

   Replace Faulty Component

   If the wiring and voltage supply are intact but the component failed bench testing, remove and replace the Y006 solenoid valve or the Y051 relay.

5. 5

   Reassemble and Power Up

   Reconnect the battery and turn the ignition on.

6. 6

   Clear Fault Codes

   The fault code must be cleared from the memory using the Fendt SERDIA diagnostic software (look for FC:004A or FC:0052). Alternatively, on many Vario terminals, you can manually delete all stored fault codes by simultaneously pressing keys D, B, and C.

7. 7

   Operational Test

   Start the engine and test drive the tractor, verifying that the engine exhaust brake and cardan brake engage properly without triggering emergency operation mode or throwing the code again.